Ketolactones

Abstract

New ketolactones of the formula I ##STR1## wherein R 1 is H, alkyl having 1-6 C atoms or aryl having 6-14 C atoms and R 2 and R 3 together are an O atom or together are a bond, and salts thereof, can be used as intermediate products in the preparation of prostaglandin derivatives.

What is claimed is: 
     
       1. A ketolactone of the formula ##STR4## wherein R 1  is H, C 1-6  -alkyl or C 6-14  -aryl or C 5-14  -aryl substituted by methyl, fluoro, chloro, methoxy, acetamido or benzamido and R 2  and R 3  together are an O atom or a single bond, or a salt thereof.   
     
     
       2. A ketolactone according to claim 1, wherein R 1  is H, methyl or ethyl. 
     
     
       3. A ketolactone according to claim 1, wherein R 1  is n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, hexyl, isohexyl, phenyl, tolyl, fluorophenyl, chlorophenyl, methoxyphenyl, acetamidophenyl or benzamidophenyl. 
     
     
       4. A ketolactone according to claim 3, wherein R 1  is p-benzamidophenyl. 
     
     
       5. 2-Oxa-4-(5-methoxycarbonylpentanoyl)-1βH,5βH-bicyclo[3,3,0]oct-6-en-3-3-one, a compound of claim 1. 
     
     
       6. 2-Oxa-6α,7α-epoxy-4-(5-methoxycarbonylpentanoyl)-1βH, 5βH-bicyclo[3,3,0]octan-3-one, a compound of claim 1. 
     
     
       7. 2Oxa-4-(5-p-benzamidophenoxycarbonyl pentanoyl)-1βH, βH-bicyclo-[3,3,0]oct-6-en-3-one, a compound of claim 4.